media/viewer: fullscreen transition animations

Signed-off-by: William Casarin <jb55@jb55.com>

crates/notedeck/src/media/action.rs

@@ -25,6 +25,12 @@ pub struct ViewMediaInfo {
     pub medias: Vec<MediaInfo>,
 }
 
+impl ViewMediaInfo {
+    pub fn clicked_media(&self) -> &MediaInfo {
+        &self.medias[self.clicked_index]
+    }
+}
+
 /// Actions generated by media ui interactions
 pub enum MediaAction {
     /// An image was clicked on in a carousel, we have